The Content Service is used if you update content nodes from your custom code, not sure if you are doing that? You could search your code for "ContentService" to see if you are using it anywhere to save or update data.

It might also be that there is stuff saved in the log that should not be presented in the dashboard - but I just want to start with making sure that you don't do any stuff in your code that creates these entries before debugging the package.

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